Conventionally, an optical-pickup feeding apparatus is configured in such a manner that a plate spring is fixed on a pickup base, a rack biased by the plate spring is engaged with a lead screw, the pickup base shifts by a rotation of the lead screw. The plate spring is structured with a plate spring A that consistently works when the lead screw rotates and with a plate spring B having an edge adjacent to a position for attaching the rack. The plate spring B does not work by a usual rotation but works for a displacement in a direction of releasing the rack from the lead screw when the rack is released from the lead screw and an engagement failure occurs. Therefore, an increase of a resistance in feeding the optical pickup and the engagement failure are prevented (see, for example, Patent Document 1).
Patent document 1: Japanese Patent Application Laid-Open No. 2002-279739